| Carbon disulfide (CSj) is widely used as a raw material or organic solvent in the manufactory of viscose rayon, in chemical and pharmaceutical industries,even in laboratories. Evidence of cardiovascular toxicity caused by CS2 has been accumulated since World War II. The mortality and incidence of coronary heart disease increased in workers who were long-term exposed to CS2. However, its injury mechanism remains elusive due to the complexity of the metabolizing process in vivo and the lag of research technique. In recent years, researches in senile arteriosclerosis have thrown light on the relationship between decreasing ability of scavenging free radicals and the disease. Results in animal experiments and epidemiologic surveys showed that cardiovascular changes related to CS2 exposure were similar to those of arteriosclerosis due to aging. The lipid peroxidates (LPO) levels in serum, aorta and myocardium of exposed animals were increased when comperism with control animals. It is suggested that CS2 is an important chemical which causes lipid peroxidation. However, it is still not clear that the capacity of free radical scavenging, the state of oxidation stress - antioxidation systems and peroxidation and theirrelation to lipid metabolism in workers exposed to CS2. And there is few reports regarding the potentiality of free radical generation both directly and indirectly and the likely forms of free radical intermediates produced by CS2 and their characteristic and related effect on bio-molecular targets. Based on the research background mentioned above, a cross sectional study of the lipid metabolism and the oxidative stress level in viscose rayon workers was performed first to explore the early influence of CS2 on integral antioxidative defense system and lipid metabolism. Then, a series of studies in vitro were employed by using chemiluminescence techniques and laser photolysis and pulse radiolysis time resolution techniques to discuss the characteristics of photochemical reaction of CS2 and its action mechanism on biological target molecules.PART ONE A Study Of Lipid Metabolism And Oxidative Stress Levels In Workers Exposed To CS2A cross-sectional study was performed based on the investigation of working environment and labor health condition. CS2 concentrations in workroom space were measured by a gas chromatography. Occupational exposure history was recorded and occupational health surveillance was carried out for workers (67 in exposure group and 88 in control group), the items included general physical examination, nerve system and eye ground examination, rest electrocardiograph, encephalon blood stream and abdomen supersonic diagram examination etc. At the same time, serum cuprozinc-superoxide dismutase (CuZnSOD, via enzyme-linked immunosorbent assay, ELASA), malonyldialdehyde (MDA, via thiobarbituric acid test, BAT) values, total cholesterol (TCH, via enzymatic test) , triglyceride (TG, via enzymatic test) levels, urine creatinine (via Jaffe's10test) and 2-thiothiazolidine-4-carboxylic acid levels were measured (by HPLC). TTCA concentration was adjusted by creatinine. A SPSS 10.0 version software package was used for statistics and age factor was controlled when partial correlation was conducted.The results showed that CS2 concentrations in workroom air were correlated with urine TTCA levels (r '=0.6869 , PO.001). Exposure to various concentrations of CS2 (0,10 and >10 mg/m3) may have different urine TTCA levels (median, 0.0088,0.4385 and 1.1980 mg/gCr), ( xMOS.527, P< 0.001).Trace TTCA can be detected in 55.7% (49/88) non-exposure people, but 95.5% (64/67) of exposure groups.When urinary TTCA levels were used as an index of CS2 exposure, (TTCA >0.5mg/g Cr, <0.5mg/g Cr), the average levels of CuZnSOD in workers exposed to carbon disulfide were higher than those of the control group (358.80 ug/L, 325.15 ug/L and 221.30ug/L, PO.001). Meanwhile, the average levels of. TCH were lower than those of the control ones (3.52, 3.68 and 3.91 mmol/L, P<0.01). In addition, TTCA...
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